Incorporation of the electrodes for defibrillation into the patient-facing components of automated cardiopulmonary resuscitation systems

Abstract

An automated resuscitation system is provided, which can improve the outcome of patients suffering ventricular fibrillation or the ventricular tachycardia variants of cardiac arrest. This outcome can be achieved by a device that integrates automatic mechanical or pneumatic capability with electrical countershock capability such that the probability of defibrillation or cardioversion with return of spontaneous circulation is increased.

What is claimed is: 
     
       1. An automated resuscitation system (ARS) comprising:
 a plurality of means adapted for applying pressure to a chest that produce forward blood flow; 
 a countershock defibrillation subsystem; 
 a plurality of countershock electrodes, wherein at least one of the plurality of countershock electrodes are located on electrode contact pressure enhancers adapted to press countershock electrodes against the chest, wherein a first portion of the plurality of means adapted for applying pressure to the chest that produce forward blood flow are the electrode contact pressure enhancers; and 
 a control system adapted to synchronize chest compressions and countershocks, wherein prior to defibrillation, compression is released by a second portion of the means adapted for applying pressure to the chest, so as to allow onset of a chest decompression, the second portion of the means adapted for applying pressure to the chest being adapted to produce forward blood flow, and wherein pressure is applied in the first portion of the plurality of means adapted for applying pressure to the chest, the first portion located over the countershock defibrillation electrodes, so as to enhance electrode contact pressure during defibrillation, whereby pressure is applied by the first portion of the means adapted for applying pressure to the chest while defibrillation current is applied to the countershock electrodes, and pressure is released in the second portion of the means adapted for applying pressure to the chest while defibrillation current is applied to the countershock electrodes. 
 
     
     
       2. The ARS of  claim 1 , wherein the plurality of means adapted for applying pressure to the chest comprises bladders adapted to encircle all or a portion of a patient's chest. 
     
     
       3. The ARS of  claim 1 , further comprising a ventilation subsystem, wherein the control system synchronizes the ventilation subsystem and the countershock defibrillation subsystem. 
     
     
       4. The ARS of  claim 3 , wherein the control system synchronizes the patterns of ventilation and electrical countershock such that electrical countershock occurs at end-expiration lung volume. 
     
     
       5. The ARS of  claim 1 , further comprising at least one biomarker sensor providing biomarker information, and wherein the controller uses the biomarker information in determining a pattern of synchronization of the chest compressions and countershocks. 
     
     
       6. The ARS of  claim 1 , wherein the plurality of countershock electrodes further comprises at least two pairs of countershock electrodes, and wherein defibrillation is achieved by multiple current paths across the chest. 
     
     
       7. The ARS of  claim 1 , wherein the countershock electrodes are incorporated into patient facing surfaces of one or more of components selected from the list consisting of circumferential constricting bladders, constricting series of bladders, constricting bands, a suction cup, a backboard, or struts on either side of the patient's thorax. 
     
     
       8. The ARS of  claim 1 , wherein the control system is adapted to increase a contact pressure on the countershock electrodes at a time of countershock. 
     
     
       9. The ARS of  claim 1  wherein the at least one means adapted for applying pressure to the chest inflates a circumferential series of bladders, wherein portions of the circumferential series of bladders over the countershock electrodes may be individually inflated. 
     
     
       10. The ARS of  claim 1 , wherein the control system is adapted to increase a force or alter a pattern of pressure on the chest based on one or more biomarker measurements selected from a group consisting of thoracic electrical resistance, ECG, EN-tidal CO 2 , and ventricular fibrillatory frequency distribution. 
     
     
       11. The ARS of  claim 1 , wherein the control system is adapted to apply countershock current along a first vector, and then transition to apply countershock current along a second vector. 
     
     
       12. The ARS of  claim 1 , wherein the means adapted for applying pressure to the chest is adapted to deliver a first compression-decompression pattern optimized for producing forward blood flow, and a second compression-decompression pattern optimized for increasing the efficacy of electrical countershock. 
     
     
       13. The ARS of  claim 1 , wherein the countershock electrodes are incorporated into the electrode contact pressure enhancers. 
     
     
       14. The ARS of  claim 1  further comprising an esophageal subsystem comprising one or more of balloons, countershock electrodes, and sensors. 
     
     
       15. The ARS of  claim 1 , wherein the first portion of the plurality of means adapted for applying pressure to the chest are configured for insertion of electrodes that are removable and disposable. 
     
     
       16. An Automated Resuscitation System (ARS) comprising:
 a circumferential constriction subsystem, the circumferential constriction subsystem comprising a plurality of constrictors adapted to performing circumferential thoracic constriction to produce blood flow, wherein a first portion of the constrictors further comprise defibrillation electrodes on a patient-facing surface of the constrictors, so that activation of the first portion of the constrictors increases the electrode contact pressure between the electrode and the patient; 
 a ventilation subsystem capable of providing inhalation and exhalation of the lungs; 
 a defibrillation subsystem capable of providing electrical countershock current to the defibrillation electrodes; 
 a controller capable of synchronizing and activating the subsystems whereby 1) a second portion of the constrictors begin to release compression at onset of a relaxation phase, 2) the first portion of the constrictors maintain or increase compression on the defibrillation electrodes after onset of the relaxation phase, and 3) the second portion of the constrictors continue to release compression, 4) the ventilation subsystem reaches and holds full exhalation, and then 5) the defibrillation subsystem applies electrical defibrillation current.